Little is known about the hotly debated subject of the effect or impact of luring birds with the aid of audio devices. What is available is scattered knowledge, often anecdotal, spread across literature and discussion groups on the Internet. There is no single-point reference or compilation of these diverse, polarized and often complicated, opinions at one place, making it even more difficult for those interested to make an informed decision on the subject.

The purpose of this article is to present - in one place - available opinion, scientific results, and laws and regulations concerning the impact of call playback on birds. Being neither a scientist nor an ornithologist, I have refrained from drawing conclusions on either the ethics or the science and have instead left it to the readers to form their own opinion on the subject. But this time based on some available inputs of relevance. My own bias is torefrain from using playback on any species that is ‘Endangered’ and to regulate playback in all protected places. However, I hope to limit the impact of my views only to the choice of illustrations which accompany this article.

♫ Call Playback:Call playback to attract birds is variously referred to as 'tape-lure', 'tape playback', 'audio playback' etc. This is a technique of playing back a sound to which a (most often unseen) bird responds by calling back and/or coming close to the the source of the sound. It can be achieved by playing back pre-recorded calls, or recording of a bird call in the field and playing it back, or by playing back a hostile call which can be a predator call or a mobbing sound. The equipment used can be tape recorders, Walkmans, mini-disc players, compact-disc players, iPod's or similar. These devices are often coupled with external speakers to boost the signal and can include the use of portable megaphones. To be effective the sound system used as an audio lure should produce 90-110 dB of sound. The Resources Inventory Committee of British Columbia's guideline for woodpecker inventory suggests that the “machine should be able to broadcast sounds over a distance of 400 meters; one technical description of a recommended player has a frequency of about 40 Hz to 12 kHz and power output of 1.2 watts at 1 kHz”[32]. The same guidelines also recommend playback of three series of 20 second calls followed by a 30 second break for a total of 2.5 minutes. However, the length/duration of playback is one of the more contentious issues surrounding the whole topic and there are as many opinions as people who comment on this aspect.

Scientists, researchers, ornithologists, bird-ringers, poachers, tour-guides and amateur birders widely and regularly use call-playback. It is known to be a particularly effective tool for bird surveys, field-experiments, migration study, bird trapping for science and for food, and often to show ‘sought-after’ and skulking endemics to paying birdwatchers.

Audio playback has been proved to have an impact on bird behaviour. Many species respond to the stimulus of conspecific activity by calling back in response, and very often coming close to the source of the sound. A field-experiment conducted in the Ebro Delta in 1993 showed that “Mist-net with tape lures were on average twice as effective as nets without tape lures” in attracting Curlew Sandpipers [48]. However, call playback is noted to have degrees of effectiveness and success is often influenced by variables like season, species, time, appropriateness, experience of the user, impact of overuse, and technical issues. Territorial response is often the most commonly elicited behaviour, though fear, hunger, and attraction of safe resting places can also be some of the factors that draw reactions to call playback.

A study of all available references, pertaining to the subject, throws up a bewildering mix of reactions and responses. There appears to be a paucity of any empirical research on the possible effects of the use of playback to attract birds, though scientists seem to use playback regularly. Many of the more descriptive inputs are from people who use playback for their own purposes, and are usually subjective or anecdotal. However, they are often the most qualified to speak on the subject as they have meaningful experiences. On the flip side are those who voice opinion without any experience and are often the ones who oppose playback on ethical grounds. There is a common ground though as no one seems to support endless playback at a single site and almost everyone seems to agree that playback should be avoided wherever species of conservation concern are involved. This does seem to suggest that, in the absence of scientifically evaluated knowledge, most feel that it is pragmatic to err on the side of caution and use common sense instead. Everyone seems to agree that good or bad, playback does indeed affect bird behaviour and is surely an intrusion.

♫ The Science and Scientists:

Exposure to call playback may have associated energy costs

As mentioned, it was not possible to trace any reviewed literature dealing specifically with the scientific study of the effects of the use of playback to attract birds. Most of the available scientific literature covers behaviour studies and adrenocortical responses using call-playback as one of the tools. Many technically qualified individuals have made personal comments on the subject, based on their experiences and some research organizations have relied on scientific inputs to frame guidelines. These are not always backed by any published literature on the subject.

Scientific studies: The available writings suggest that responding to call-playback may incur energy costs, disrupt social systems, lead to pair break-ups and cause stress. Some of the more relevant are extracted below:

♪ A study conducted by Professor Martin Wikelski of the University of Illinois on Spotted Antbirds in Panama found that male antbirds increased their testosterone levels and became more aggressive, even in a sexually inactive period, when confronted by a prolonged (2 hrs) playback of recorded sounds made by potential enemies. Professor Wikelski goes on to say “it makes sense for birds to maintain a baseline level of aggression without testosterone, because testosterone has costs, such as higher mortality rates”.[19, 25][Similar studies on bush warblers (Cettia diphone) in Japan[21] suggest that adrenocorticosteroid responses to stress may vary according to location (tropics vs temperate regions) and territorial and parental behaviour and results of such experiments may not be generalized.]

There is also "evidence that prolonged high levels of circulating testosterone may incur costs that may potentially reduce lifetime fitness" ~ Avoiding the 'Costs' of Testosterone: Ecological Bases of Hormone-Behavior Interactions by John C Wingfield & others.[18]

♪ Daniel J. Mennill of the University of Illinois led a team that conducted a study on 'female eavesdropping on male song contests in songbirds'[15] using call playback. The results showed that female Black-capped Chickadees eavesdrop on male song contests to make extra-pair mating decisions following simulated playback defeats of their partner. Dr. Mennill also found that “... high-ranking males who lost song contests also lost paternity in their nests.” and “ Finally, our results show that short playback sessions can have long lasting and far-reaching effects on individual fitness.”[15, 22]

Paul McDonald comments on the same study in the Birding Aus forum “The point is that with only a very short playback period (...), the authors triggered females to drastically change their reproductive behaviour. Likewise, it has been shown in many species that other males also eavesdrop on these interactions, and the 'loser' may be prone to more intrusions from adjacent males, as his quality may be inferred to be lower than it actually is following an experimental defeat. Thus, by continually playing calls in the one territory, I suspect birders are effectively simulating the resident bird 'losing' to the tape/mp3 player that it fails to evict from its territory.”[27]

Similar results were obtained by Dr. Jeffrey R. Lucas, Professor, Dept. of Biological Sciences, Purdue University on studies conducted on Carolina Chickadees. He found that it was “very common for us to instigate territory disputes”.. “because responses that we elicit from one neighbor are usually reacted to by other neighbors”. He believes that these increased interactions may potentially have a disruptive effect on social systems. Dr. Lucas's comments were shared on the NEOORN discussion board[6].

♪ Paulo Gama Mota, Director, Museum of Science, University of Coimbra, Portugal conducted a 'test of the effect of male song on female nesting behavior in the Serin (Serinus serinus)' in a field playback experiment. He found that that females who listened daily to playbacks of male songs, during the nest-building stage, spent about 30% more time nest building than females that were not thus exposed. Incidentally, male song is known to “stimulate female reproductive activity, affecting their behavior and physiology, such as follicular growth, nest building and egg laying”.[49]

Several field studies have shown that playback of songs are sufficient stimuli to evoke behavior which normally occurs in response to the singing of another bird (e.g., Weeden and Falls, 1959; Stein, 1963).

♪ Playback experiments conducted by Dr. K. Yasukawa and others on Red-winged Blackbirds showed that territorial males can discriminate between neighbours, strangers and self songs and react differently to each and “stranger song elicited significantly more intense Song Spread displays than did self song”.[16] (Tape-luring depends heavily on playback of 'stranger' songs/calls – Ed.)

♪ Studies conducted by Dr. Shallin D. Busch of the University of Washington, Seattle on the reproductive endocrinology of the song wren (Cyphorhinus phaeocephalus) using conspecific playback to simulate a territorial intrusion showed that such use resulted in an increase in Luteinizing hormone and testosterone in the territorial male.[20]

♪ Playback of colony sound tests in Zebra Finch (Taeniopygia guttata) colonies conducted by Dr. Joseph R. Waas of the Department of Biology, Queen’s University, Ontario and others to test the hypothesis that “social stimulation, derived from the presence and activities of conspecifics, can hasten and synchronize breeding in colonies of birds” [24] found that such stimulation influenced the breeding schedule and clutch sizes positively.

♪ Speaker-replacement studies by Krebs (1977) showed that song playback affected space use in free-living birds. [We have been unable to access this paper - Ed].

Comments by Scientists: Many scientists and ornithologists have made personal comments on various forums. There are also comments attributed to those who study birds. Many of these comments were contributed to an enlightening discussion on the subject entitled “Audio playback: impact on Neotropical birds?”[6] initiated by Stephen M Smith of the Department of Biology, University of Waterloo, Canada on the NEOORN[26] discussion board. Another meaningful discussion took place on the Birding Aus mailing list which was a source of additional inputs. Appended are a selective extract of comments/remarks:

♦ Paul G. McDonald, Lecturer and Macquarie University Research Fellow (Birds AUS post,16 Sep 2008)[27] : According to Dr. McDonald playback affects bird behaviour subtly, though energy wastage “as a direct result of playback is probably not very important....”. It is the possibility of long-lasting negative effects of limited playback that are more a cause for concern. These effects may include loss of clutch paternity for resident males and energy expenditure to defend territory even after the playback ceases. He is “not aware of any papers that test this directly, and this is unlikely to lead to any conservation issues. However, it does raise ethical concerns, as the results from the playback may continue well beyond the point birders have left the area”.

♦ Bruce W. Miller, Associate Conservation Zoologist, Wildlife Conservation Society, Gallon, Belize (NEOORN post[6], 22 March 2005): Dr. Miller states that “.... many bird species formerly common are no longer to be found in the same locations where some guides ...... play tapes for 15–20 min without stop”. The birds, however, continue to be found in similar undisturbed habitats. His observations are based on records kept over a period of 14+ years.

♦ Alvaro Jaramillo, Senior Biologist, San Francisco Bay Bird Observatory and professional tour guide leader (NEOORN post[6], 22 March 2005): Mr. Jaramillo has used playback on tours as well as in scientific contexts. He believes that “tape playback is harmless” and the territory holding male emerges the victor in the duel There is an impact on behaviour, “but then it is much better than people trampling vegetation or trying to sneak up on birds...”.

♦ Bridget Stutchbury, Professor and Canada Research Chair, York University, Toronto. Author of 'Silence of the Songbirds' (NEOORN post[6], 28 March 2005): Dr. Stutchbury agrees that playback is to be generally discouraged unless it is used specifically for formal data collection and/or research. According to her, “Recreational playbacks for birding can be harmful if done repeatedly to the same pairs of birds; and it’s unnecessary”.

♦ Bruce Falls, Ornithologist and Professor of Zoology, University of Toronto (NEOORN post[6] , 31 March 2005): According to Dr. Falls, playback is a valuable tool for both research and counting and its use in moderation is justified with the gains outweighing any downsides. His field experiences with White-throated Sparrows and Meadowlarks showed that effect of playback was 'negligible' and the birds "habituated”. Dr. Falls goes on to add that “However, I do have concern for rare birds that are repeatedly assaulted by playback from a succession of groups at the same site. Habituation may limit the damage but I would prefer to err on the side of caution”.

♦ Phil Taylor, Professor, Acadia Biology Department Chair, ACWERN, Nova Scotia (NEOORN post[6], 24 March 2005): Dr. Taylor does not consider careful use of playback to be a “big issue”. He is, however, concerned about the “disruptive” or possible “detrimental” impact of excessive playback or repeated playback aimed at individuals or pairs.

♦ Kathryn E. Sieving, Professor, Wildlife Ecology and Conservation, University of Florida (NEOORN post[6], 25 March 2005): According to Dr. Sieving, audio playback has an impact on (neotropical?) birds. The impact she is aware of is the “increased risk of predation on individuals responding to playbacks”. She gives an example of playback-research studies in Chile, where predatory birds attacked birds responding to conspecific territorial calls. Dr. Sieving goes on to add that “More and more people will be using this technology, and we have to moderate it at some point.”

♦ Jeffrey R. Lucas, Professor, Dept of Biological Sciences, Purdue University (NEOORN post[6], 25 March 2005): Dr. Lucas's comments on the potentially disruption of bird social systems by the use of playback has been described above. He also goes on to say that “The point is that there are lots of ways to disrupt a social system through playbacks, and to do this in order to let some people see a rare bird seems a bit much.”

♫ Birdwatchers and like: Bird lovers, birders, bird photographers are the one's who often use call playback or have been around to see the effects of lures. They have expressed opinion in various forums based on their own feelings on the subject. Many have expressed surprise at the lack of any scientific study which would have enabled them to take an informed decision on the subject. Some felt that it was unethical to intrude but some others felt that birdwatching itself is an intrusion and call playback is only an extension of it and, therefore, as acceptable as any other process of disturbing birds.

Presented below is a cross-section of some representative opinions culled from the Web:♣ Dennis Rogers, 22 March 2005, NEOORN[6]: “No matter the conservation value of the area in question or the science available to judge impact of playback use, the fact is a tiny proportion of the local or global population is likely to be affected. So the conservation importance is negligible.”♣ Rasmus Boegh, 18th April 2005, Birdforum[7]: “Special caution should be taken when dealing with rare birds or birds during the breeding season, and regularly a complete "no" to playback may be the best approach in those situations. In areas where playback is used more or less continuously, it has been observed that birds get "played out". The fact that their behaviour is significantly altered should be enough to ban it completely in those cases.”♣ Ian, 20th April 2005, Birdforum[7]: “I think using playback reduces disturbance on habitat and bird populations as a whole, since birders head for a stake out and focus their attentions on one area/pair of birds.”♣ Alf King, 20th April 2005, Birdforum[7]: “In my personal opinion I don't like to see tapes being used, especially just for a "quick tick" for which I believe some (not all) visiting birders may be guilty.”♣ Nigel Blake,18th April 2005, Birdforum[7]: “While I personally would not use taping I don't really see that taped calls would have any different effect than that of a rival bird singing in the area.”♣ Jos Stratford, 20th April 2005, Birdforum[7]: “I agree with the general consensus - an isolated, one-off use of a tape lure probably is of little consequence to an individual bird, but repeated use is more likely to be an issue.” ♣ SheffieldPete, 28th Jan 2008, Wild About Britain[10]: “Tape luring is a pretty frowned upon practice, as it stresses birds something rotten and can seriously disrupt breeding.”♣ KnockerNorton, 4th February 2008, Birdforum[8]: “ If you stand there for half an hour, blasting out a tape, it's not a good idea. But used for a few minutes to check presence / get an i.d. isn't going to do any harm in most cases. Calling down migrants to unsuitable areas is questionable, or harassing migrants at the coast.”♣ J Moore, 14th February 2008, Birdforum[8]: “I think the big problem comes in heavily birded areas, or where a bird difficult to see is known to be in a particular area. Those situations present the potential for multiple birders to be playing recordings of the same bird on a frequent basis over an extended period. If that happens, the playing of recordings may seriously disrupt the bird's natural behavior."♣ Richard Klim, 17th February 2008, Birdforum[8]: “I have seen examples where birders who are totally against the use of tapes will instead spend many hours wandering repeatedly through fragile habitat, ..., causing untold damage and seriously disrupting the normal routines of countless birds.”♣ gyrfalcon, UK, 17th February 2008, Birdforum[8]: "Is the birder seeing the bird more important than the perceived stress and disturbance to the bird?".♣ Graham, 21st May 2008, Birdforum[9]: “....it's just cheating, isn't it? Where's the satisfaction in luring birds when it achieves nothing a bit of fieldcraft and patience won't also deliver? .... I can't understand how people are pleased with sightings achieved this way.”♣ Sancho, 22nd May 2008, Birdforum[9]: “On the tape-lures issue, I'm no expert but I'm uncomfortable with it. We don't know what bird-song really means. Playing a recording to a nesting bird especially could affect its behaviour,..”.♣ Hanno, 23rd May 2008, Birdforum[9]: “I have no qualms using a recorder here in Vietnam. There are hardly any birders, I use it only for a short time each time, and without playback there is little chance of seeing some of the skulkers.” ♣ KnockerNorton, 21st May 2008, Birdforum[9]: “, ...but playback in itself is neither unethical nor unacceptable.”♣ Chris Sanderson,16th September 2008, Birding-Aus[11]: “..in situations where playback still works it is likely you are causing the birds stress. How much stress, and whether that has long-term survival impacts needs research.”♣ Douglas Carver, USA, 15th September 2008, Birding-Aus[11]: “I have taken courses with two different ornithologists at the Smithsonian Institution. Both cautioned against using playbacks, except in rare instances, and even then using then sparingly (...). While neither had hard empirical data (...), they both said that a bird responding to a call is expending energy needlessly, which puts unnecessary stress on the bird.”♣ Rich Hoyer, USA, 15th September 2008, Birding-Aus[11]: “... though I have years of tape playing experience, and I'm pretty convinced it doesn't have much of an effect on birds, it's not something I recommend very highly. Often birds don't respond, so you've wasted time you could have spent looking for other birds. It's distracting and noisy (...). And the response you get is uninteresting and sometimes even makes the bird harder to see than if you had just waited a bit."♣ Dan Bieker, who’s been teaching Field Ornithology at Piedmont Virginia Community College, on a live broadcast on the 'Birding Ethics'[30] conducted by Nancy King on August 17, 2007 (VFH Radio), had this to say to the question 'is (playback) so good for the bird?': “no”. “It disrupts the birds. A lot of these birds are right on the edge of survival. And to disturb them like that, um, raises some ethical questions.” John Spahr, Former Virginia Society of Ornithology president, had this to say in the same programme: “If one is cautious and limits the use of audio recordings, I think that’s perfectly acceptable.”[30]♣ A blog post dated 4th June 2009 by Ruth K. quotes Mike Burrell, an experienced birder and researcher thus: “As far as bird song playback goes. It certainly stresses a bird. But, so does pishing, squeaking, etc. ....”[37]♣ Dr. Peter May in a 'Screech Owling' article written for Nature Photographers relates his experience of playback of owl tapes attracting predatory birds to the mobbing flock due to the concentration of prey. In his opinion “Overuse of tape playback to attract birds can be detrimental to the survival and reproduction of some species by preventing them from devoting full attention to other biological demands, such as feeding their offspring.”[36]

♫ Lawmakers, Regulators & Conservation bodies:There are no blanket prohibition or sweeping restrictions, in any country, on the use of call playback to lure birds – at least I did not find any after searching widely. There are location specific, playback volume, season, time of day, and species risk based bans. Use of restrictions to control call playback is more widespread and prevails in many areas and locations. The most sweeping is the law in the United States of America which prohibits the use of playback devices which cause unreasonable disturbance at all National Wildlife Refuges. The regulations that apply to National Parks prohibits playback exceeding 60 decibels. In the United Kingdom, it is considered a offence to disturb, intentionally or recklessly, at or near the nest, a species listed on Schedule1 of the Wildlife & Countryside Act 1981. Disturbance could include playback of songs and calls. Other than these, various countries/locations have imposed need-based restrictions which can be blanket - like in Sri Lanka, where playback is prohibited in the Sinharaja Wilderness Area, or be species based like the one in Water Treatment Plant in Australia where call-playback for any species of crake or rail is not permitted.

Appended below is a list of some of these restrictions/prohibitions:

♠ United States Fish and Wildlife Service. Department of the Interior. Subchapter C: The National Wildlife Refuge System. Part 27-Prohibited Acts. Subpart G—Disturbing Violations: Light and Sound Equipment: § 27.72 Audio equipment: “The operation or use of audio devices including radios, recording and playback devices, loudspeakers, television sets, public address systems and musical instruments so as to cause unreasonable disturbance to others in the vicinity is prohibited.”[1]

♠ Code of Federal Regulations; Title 36 -- Parks, Forests, and Public Property; Chapter I – National Park Service, Department of the Interior; Part § 2.12 Audio disturbances: “(a) The following are prohibited:(1) Operating motorized equipment or machinery such as an electric generating plant, motor vehicle, motorized toy, or an audio device, such as a radio, television set, tape deck or musical instrument, in a manner: (i) That exceeds a noise level of 60 decibels measured on the A-weighted scale at 50 feet; or, if below that level, nevertheless; (ii) makes noise which is unreasonable, considering the nature and purpose of the actor's conduct, location, time of day or night, purpose for which the area was established, impact on park users, and other factors that would govern the conduct of a reasonably prudent person under the circumstances.”[2]

♠ "In England, Scotland and Wales, it is a criminal offence to disturb, intentionally or recklessly, at or near the nest, a species listed on Schedule 1 of the Wildlife & Countryside Act 1981. Disturbance could include playback of songs and calls. The courts can impose fines of up to £5,000 and/or a prison sentence of up to six months for each offence."[3]

♠ The Royal Society for the Protection of Birds (RSPB)'s own guidelines go thus: “Repeatedly playing a recording of birdsong or calls to encourage a bird to respond can divert a territorial bird from other important duties, such as feeding its young. Never use playback to attract a species during its breeding season.”[4]

♠ The American Birding Association's (ABA) Code of Birding Ethics recommends the following: 1(b) “.... Limit the use of recordings and other methods of attracting birds, and never use such methods in heavily birded areas. or for attracting any species that is Threatened, Endangered, or of Special Concern, or is rare in your local area.”[5]

♠ Arizona Game and Fish Department's pages on the Elegant Trogon Trogon elegans states that “of tape recorders and other call-back mechanisms to entice a trogon into better view, can effect nesting success. (Johnson 2000).”[38] and conservation measures introduced include restrictions on 'tape-recorded trogon calls used to lure the birds into view'.[29]

♠ At the Great Dismal Swamp National Wildlife Refuge, USA “Playback recorders or devices are prohibited because they adversely affect wildlife behavior”.[40]

♠ The Matagorda National Wildlife Refuge, USA website requests that: “Please help us protect the natural avian communities in our parks by refraining from using playback tapes of bird songs. Frequent use of these tapes disrupts normal avian activity patterns, disrupts essential territorial behavior and may lead to nest failure.”[41]

♠ Big Woods area, USA : “Playback tapes or any method of producing Ivory-billed Woodpecker vocalizations and double knock sounds are not permitted on any of the federal, state, and non-government organization lands in the Big Woods. Producing these sounds could affect Ivory-bill behavior and alter the findings of the ongoing research.”[42]

♠ Galapagos National Park bans use of tape lures.[39]

♠ Sinharaja Wilderness Area prohibits tape playback: “A new threat that has an adverse effect on the avifauna is the “commercialization of bird watching”. The use of tape lures to attract rare and elusive birds (mostly endemics) to be shown to foreign visitors by using breeding or communication calls has clearly had its impact. The practice, on the merit of clear evidence, resulted in prohibiting tape lures within Sinharaja Wilderness Area.”[34]

♠ Queensland's 'Nature Conservation (Protected Areas Management) Regulation 2006 – Sect139' states: “A person must not use a radio, tape recorder or other sound or amplifier system in a way that may cause unreasonable disturbance to a person or animal in a protected area.”[46]

♠ Byron Bay Integrated Water Management Reserve, Australia requires that “Permit holders are not to employ call-playback for any species on site without Councils permission.”

♠ “Permit holders are not use ‘call-playback’ for any species of crake or rail at the Western Treatment Plant. This condition arises from expert advice provided to Melbourne Water”[47]

♠ The British Trust for Ornithology - Guidelines for Constant Effort ringing in Europe: “Tape lures are not permitted on constant effort sites at any time during a visit because they may disrupt normal bird activity.”[12]

♠ The Ornithological Council, Washington in their ' Guidelines to the Use of Wild Birds in Research* ' state that: “Playback of tape-recorded vocalizations to free-living birds causes little disturbance or trauma if the duration of the playback is kept within reasonable bounds (normally less than 30 minutes). More prolonged playback may distract subjects from activities that are essential to reproductive success. Unless required for the experiment, speakers should not be placed close to the nest, etc. ....”[13].[* Note: A major revision of the Guidelines is expected to be posted by the end of 2010; TOC - pers comm 25/12/10]

♠ British Columbia’s Ministry of Environment Lands, and Parks protocol for woodpecker inventory states that “Playback surveys are suitable for species that respond readily to recordings, occupy relatively large home ranges and/or are otherwise difficult to detect.”[32]

♠ Guidelines for Nocturnal Owl Monitoring in North America. Beaverhill Bird Observatory and Bird Studies Canada, by D. Lisa Takats and others recommend that playback protocol for survey is optional and “Playback can also potentially be disruptive to owls (may increase risk of predation, disrupt foraging and courtship, and/or draw females off nests). In addition, playing calls can pull owls off their territories giving inaccurate information on their habitat use (Holroyd and Takats 1997).”[31]

♫ Published notes / reports / articles:♥ TRAFFIC's bulletin on 'The Illegal Trade in Wild Birds for Food' highlights the ill-effects of playback use: “Hunters targeting small birds for the food trade often use illegal hunting methods to maximise the number of birds killed in each attempt. Illegal methods include the use of recordings to attract birds – ‘tape lures’, .....”. “38,000 Common Quail Coturnix coturnix were shot in Serbia during two months in 2004 – more than the entire breeding population of Serbia. It is estimated that over 90% were shot illegally, using tape lures and semi-automatic shotguns.”[35]

♥ In Tamil Nadu, India trappers around Nagapattinam have been known to use speakers attached on trees to trap wild birds for food.[43]

♥ BirdJam, a bird song identification tool maker for the Apple iPod® provide recommendations to birders for responsible use of BirdJam iPod's. Written by Sharon Stiteler, the recommendations stress against repeated playback to elicit response and warn against continuous playback “during the breeding season when you might get both male and female birds agitated and away from the nest. That's when predators, competitors and cowbirds would have an opportunity to find the nest unguarded.”[44]

♥ Cornell Lab of Ornithology's 'Birds in Forested Landscapes' program provide a protocol for 'Playback use and responses'. These include recommendations on duration of call playback - 'two one-minute segments for playback or five minutes for the mobbing call' and state that the playback protocol “'must be standardized, and it is important not to stress territorial birds.” The protocol concludes that “The birds might appear agitated in response to the mobbing calls, but we feel that this five-minute mobbing sequence will be less invasive than searching the forest for nests.”[45]

♫ Summary▼ Call playback has wide usage in drawing response from birds. ▼ There appears to be no published empirical study to determine the effects of playback. This has led to the absence of uniform guidelines to explain the impact and regulate the use. ▼ Call playback is a source of disturbance and affects birds in different degrees. However, such impact may be marginal and may not be of significance. ▼ Continuous playback and playback targeted at rare and endangered birds should be avoided till we understand the effects better.

This is what we know. In the end it is for you to judge for yourself!

♫ Some Comments received:§12th November 2009: "The call play back should not be allowed at all. It is certainly harmful for territorial birds and breeding birds". Dr. Girish Jathar§19th November 2009: A helpful summary of the diversity of information and views to date. This should stimulate some serious research into the subject, without which we are simply speculating.§ 21st December 2009: Wonderful unbiased article... Human footprint on bird habitat can actually be made smaller with the judicious use of technology..........____________________________

Sumit SenKolkata, IndiaNovember, 2009I make no claims that my views are those of the 'Birds of India' website or those associated with it.